1. Field of the Invention
This invention relates generally to a customer replaceable unit (CRU) for a printing machine, and more particularly concerns a CRU container as typically used in an electrophotographic printing machine that can be easily and quickly replaced.
2. Description of the Prior Art
In a typical electrophotographic printing process, a photoconductive member is charged to a substantially uniform potential so as to sensitize the surface thereof. The charged portion of the photoconductive member is exposed to a light image of an original document being reproduced. Exposure of the charged photoconductive member selectively dissipates the charges thereon in the irradiated areas. This records an electrostatic latent image on the photoconductive member corresponding to the informational areas contained within the original document. After the electrostatic latent image is recorded on the photoconductive member, the latent image is developed by bringing a developer material into contact therewith. Generally, the developer material comprises toner particles adhering triboelectrically to carrier granules. The toner particles are attracted from the carrier granules to the latent image forming a toner powder image on the photoconductive member. The toner powder image is then transferred from the photoconductive member to a copy sheet. The toner particles are thereafter heated to permanently affix the powder image to the copy sheet.
In printing machines such as those described above, a CRU container is a customer replaceable unit which can be replaced by a customer. CRUs, particularly xerographic CRUs, typically include toner container (i.e. bottles), (e.g. waste toner or new toner), cleaner waste bottles or humidifier waste bottles. For purposes of ease of describing the present invention, the example will constantly be given of toner containers or bottles. However, it is to be understood that the present invention is a unique design for any CRU container or bottle as typically used in a printing machine such as a xerographic printer and therefore can include, toner bottles, cleaner solution bottles or any other CRU bottle used in such machines. In addition, the terms xe2x80x9ccontainersxe2x80x9d and xe2x80x9cbottlesxe2x80x9d as used herein are equivalent to each other.
In the process of electrophotographic printing, the step of conveying toner to the latent image on the photoreceptor is known as xe2x80x9cdevelopmentxe2x80x9d. The object of effective development of a latent image on the photoreceptor is to convey developer material to the latent image at a controlled rate so that the developer material effectively adheres electrostatically to the charged areas on the latent image. A commonly used technique for development is the use of a two-component developer material, which comprises, in addition to the toner particles which are intended to adhere to the photoreceptor, a quantity of magnetic carrier granules or beads. The toner particles adhere triboelectrically to the relatively large carrier beads, which are typically made of steel. When the developer material is placed in a magnetic field, the carrier beads with the toner particles thereon form what is known as a magnetic brush, wherein the carrier beads form relatively long chains which resemble the fibers of a brush. This magnetic brush is typically created by means of a xe2x80x9cdeveloper rollxe2x80x9d.
Another known development technique involves a single-component developer, that is, a developer which consists entirely of toner. In a common type of single-component system, each toner particle has both an electrostatic charge (to enable the particles to adhere to the photoreceptor) and magnetic properties (to allow the particles to be magnetically conveyed to the photoreceptor). Instead of using magnetic carrier beads to form a magnetic brush, the magnetized toner particles are caused to adhere directly to a developer roll.
The present invention can be employed with either of the above known development techniques.
In an electrophotographic printer as the toner within the developer material is transferred to the photoreceptor and eventually to the copy paper, this used toner must be replaced. The electrophotographic printer thus includes a toner container (i.e. cartridge or bottle) from which fresh toner is dispensed into the machine. When using two component developer, a portion of the carrier granules will eventually deteriorate. Additional new carrier granules may be added to the machine to replace the deteriorated granules. The toner bottle may thus alternatively store a mixture including a small quantity of carrier granules in addition to the toner. To provide for a small compact toner bottle and to provide for a toner bottle which the opening to the bottle may be easily removed, the toner bottle typically has a compact shape with a small opening from which the toner is dispensed.
Traditionally when all the toner within a bottle has been consumed, additional toner is supplied to the machine by pouring toner from a separate refilling container into the bottle. This method permits many toner particles to become airborne during filling and enter the machine. The operator may even miss the opening of the container during filling and spill large quantities of toner inside the machine. Since the toner is inherently very susceptible to electrostatic charges, the toner sticks electrostatically to all the remote recesses of the machine making cleaning of the machine necessary. This cleaning process is both time consuming and expensive.
Xerographic machines have therefore been supplied with replaceable toner containers to avoid some of the problems associated with spilling toner during refilling. While missing the opening of the container during filling and spilling large quantities of toner is alleviated by replaceable toner containers, spillage can occur from the old container during removal and from new container installation.
Toner in the toner container must be fed to the latent image to effectuate development. Typically, toner containers are located with their openings in the bottom of the container whereby they may be emptied by gravity. In view of the general manner that these kinds of containers are used in xerographic printers it would represent a major advantage to have a CRU container that would generally reduce the number of steps required to disengage, remove and replace disposable containers with screw-on types of mating mechanisms positioned inside of the machine. Prior attempts to design toner and other containers for use in a xerographic printer such as an electrophotographic printer which offer these advantages and can function as a CRU in these kinds of environments have not generally be completely successful.
In accordance with one aspect of the present invention, there is provided a container assembly for storing material for delivery to or from a printing machine comprising a container having a chamber for storing the material and a first mouth member, the container releasably co-operable with a conduit device having a second mouth member projecting therefrom and a screw-on mating mechanism positioned on the second mouth member, the container including a plurality of bump-like projections adapted to lift the mating mechanism so as to easily permit the container to be inserted into or removed from the machine and also easily permit the first mouth member to be in contiguous relation to the second mouth member, whereby the screw-on mating mechanism is adapted to screw securely the container to the device permitting the material to flow between the container and the device.
Another aspect of the present invention provides a container assembly for storing a supply of particles for use in a developer unit of an electrophotographic printing machine comprising a container having both a chamber for storing the particles and a first mouth member, the container being releasably co-operable with a conduit device having a second mouth member projecting therefrom and a screw-on mating mechanism positioned on the second mouth member, the container including a plurality of bump-like projections adapted to lift the mating mechanism so as to easily permit the container to be inserted into or removed from the machine and easily permit the first mouth member to be in contiguous relation to the second mouth member, whereby the screw-on mating mechanism is adapted to screw onto the first mouth member and secure the container to the conduit device permitting the particles to flow between the container and the conduit device.
Another aspect of the present invention provides a developer unit for developing a latent image recorded on an image receiving member in a printing machine with a supply of particles, comprising a conduit device cooperable with a mechanism to feed the particles from a first mouth member on the device into the development unit, the conduit device including a screw-on mating mechanism adapted to screw onto the first mouth member; and a container defining a chamber for storing particles therein, the container having a second mouth member extending therefrom and a plurality of bump-like projections adapted to lift the mating mechanism so as to easily permit the container to be inserted into or removed from the machine and easily permit the second mouth member to be in contiguous relation to the first mouth member, the container adapted to be releasably cooperable with the device by fitting the first mouth member on the second mouth member and turning the mechanism to screw the mating mechanism onto both the first and the second mouth members whereby the container is firmly secured to the device.
Still another aspect of the present invention relates to an electrophotographic printing machine for developing with a supply of particles a latent image recorded on an image receiving member, the printing machine including a developer unit, the developer unit comprising a conduit device cooperable with a mechanism to feed the particles from a first mouth member on the device into the development unit, the device including a screw-on mating mechanism adapted to screw onto the first mouth member, and a container defining a chamber for storing particles therein, the container having a second mouth member extending therefrom and a plurality of bump-like projections adapted to lift the mating mechanism so as to easily permit the container to be inserted into or removed from the machine and permit the second mouth member to be in contiguous relation to the first mouth member, the container adapted to be releasably cooperable with the device by fitting the first mouth member over the second mouth member and screwing the mating mechanism onto the second mouth member whereby the container is firmly secured to the device.
Furthermore, another aspect of the present invention relates to a method for inserting and securing a container within a printing machine comprising the steps of inserting within the machine a container having a first mouth member and a plurality of bump-like projections, both the first mouth member and the projections extending from the top portion of the container; moving the first mouth member towards a conduit device in the machine, the device having a second mouth member projecting therefrom and a screw-on mating mechanism positioned on the second mouth member, the mating mechanism adapted to be in a screw fitting relation over the second mouth member; employing the bump-like projections to permit the second mouth member to remain in a position in the machine so as to allow the container to be pushed into the machine in a straight direction and position the first mouth member such that it is in contiguous relation to the second mouth member; and rotating the screw-on mating mechanism to screw onto both the first mouth member and the second mouth member thereby firmly securing the container to the device.
In accordance with the features of the present invention, there is described a customer replaceable unit (CRU) in the form of a cartridge container having a unique design that will reduce the total number of process steps that are required to disengage, remove and replace disposable containers with screw on mating mechanisms positioned inside of a printing machine. The unique design is for containers that pull out of the printing machine, but the screw-on mating mechanism which securely holds the container in the printing machine remains positioned inside of the printing machine.
In accordance with one preferred feature of the present invention, a container has been designed to have molded in bumps positioned on the exterior surface of the container to enable the action of pulling and/or pushing the container to cause the mating mechanism to lift over the mouth of the container thereby making it easier to place a container into or remove it from the printing machine, i.e. in a substantially straight direction.
In accordance with another preferred feature of the present invention, there is included a design for a finger actuated screw-on mating mechanism, i.e. the mechanism which tightens the grip onto the container so as to position the container within the machine to eliminate the need for a whole hand actuation of the mating mechanism inside the machine.
In accordance with still another preferred feature of the present invention, a screw-on mating mechanism is employed which is positioned and remains positioned within the printing machine.